Conventionally, a pneumatic tire for a motorcycle having a spiral belt between a carcass and a tread rubber is known (see patent documents 1 to 6 for example). In the examples described in patent documents 1 to 4, a spiral belt is formed by coating a belt cord with rubber, and in order to enhance the high-speed durability and steering stability, the number of cords embedded in the spiral belt is varied (increased) from a center area to shoulder areas. In the examples described in patent documents 5 and 6, the number of cords embedded in the spiral belt is the same from the center area to the shoulder areas, rubber having excellent high-speed durability is provided at the center area, and rubber having excellent turning performance is provided at the shoulder area.
Patent Document 1: Japanese Patent Application Laid-open No. 6-40210
Patent Document 2: Japanese Patent Application Laid-open No. 9-118109
Patent Document 3: Japanese Patent Application Laid-open No. 10-81111
Patent Document 4: Japanese Patent Application Laid-open No. 10-86608
Patent Document 5: Japanese Patent Application Laid-open No. 61-27707
Patent Document 6: Japanese Patent Application Laid-open No. 7-108805